Polycarbonate polyols are excellent in transparency, heat resistance, and mechanical strength, and are widely used in industries such as electrical and electronic parts, automotive parts, optical recording media, and lenses.
The conventional polycarbonate polyol process, however, is carried out by transesterification of an organic carbonate and a polyol at a specific pressure (1.5 to 100 bars) and temperature (100° C. to 300° C.). Alcohols such as methanol (depending on the type of organic carbonate) and unreacted carbonate are distilled off. In the reaction, a catalyst containing an alkaline earth metal or transition metal is added. The residues of these catalysts affect the product properties of the polycarbonate polyol. Accordingly, the selection and use of catalyst must be carefully evaluated. Therefore, it is necessary to develop a catalyst that can be easily removed in the process, or to develop a catalyst that remains in the product without affecting its properties.